The invention concerns a radiation protection material for shielding X-rays and/or gamma rays made from a foil-like, multi-layer material in which ray-absorbing particles are dispersed.
Foil-like materials for the production of X-ray protection aprons and other radiation-absorbing applications are conventionally produced with the addition of metallic lead powder or also lead salts such as oxides or sulfides and polymers such as e.g. PVC plastisol, EVA copolymers or caoutchouc. However, lead is considered to be a toxic substance. So-called lead aprons moreover have a weight which impairs the activities of the persons wearing them.
Prior art discloses some products which attempt to avoid these disadvantages. WO 93/11544 discloses e.g. a radiation-resistant film having a thermoplastic elastomer which contains between 60 and 90 weight % of barium sulfate or a different barium salt.
EP 0 371 699 A1 discloses an energy-absorbing material comprising a layer which consists of a polymer composition having 7 to 30 weight % of a specific polar thermoplastic polymer, 0-15 weight % softener and 70 to 93 weight % of an inorganic composition. The inorganic composition thereby consists of at least two elements which are supposed to provide better protection from radiation than lead.
Moreover, EP 0 372 758 A1 discloses a material which consists of 4 to 19 weight % of a polar thermoplastic polymer, 0 to 10 weight % of a softener and 81 to 96 weight % of an inorganic compound.
Further flexible multi-layer X-ray protection materials are disclosed in G 94 02 609.2 and DE 201 00 267 U1.
DE 199 55 192 A1 discloses a method for producing a radiation protection material using a thermoplastic, vulcanisable elastomer to which a metal powder is added.
U.S. Pat. No. 6,153,666 discloses a polymer matrix with embedded metal for shielding X-rays, wherein the polymer matrix is a plastified non-elastomeric polymer.
It is the underlying purpose of the invention to present a radiation protection material which provides high radiation protection over a wide application and energy range, with the material having low weight and high flexibility.